Unless in London, £1k for a standard single storey extension is a lot.
If it included structural beam design, or any sort of non-standard designing of the actual extension, then it may be OK as that will take extra time. But if its just a box on the back of the house and a knock through, then £400-£500 would be about right .... it seems that he's not even going for planning permission, just b/regs
If its a standard semi, the guy has probably done loads of these and will just have to change the address and print out the plans
If it included structural beam design, or any sort of non-standard designing of the actual extension, then it may be OK as that will take extra time. But if its just a box on the back of the house and a knock through, then £400-£500 would be about right .... it seems that he's not even going for planning permission, just b/regs
If its a standard semi, the guy has probably done loads of these and will just have to change the address and print out the plans